3. Red-Crested Tree Rat

The red-crested tree rat lives in the forests of Colombia. It was thought to be extinct for many years — until volunteers at the El Dorado Nature Reserve were visited by the creature in 2011. The last recorded sighting was in 1898, when two of the critters were found and studied, and were the subsequent source of all information about the rat.

This little critter is about 18 inches long, which is about the same size as a guinea pig. It inhabits a relatively small area of the forest in Colombia, and much of this area has been cleared or disturbed.

4. Angel Shark (aka Squatina Squatina)

Historically, the angel shark range was from the Northeast Atlantic, Mediterranean, and Black Seas, but commercial fishing has diminished the population. It is now uncommon throughout most of its range with the exception of some areas of the southern Mediterranean and Canary Islands.

8. Gooty Tarantula (aka Metallic Tarantula)

The spider’s habitat is in Southeastern India and Sri Lanka. Habitat loss and degradation as a result of deforestation, firewood collection, and civil unrest have all contributed to the loss of this tarantula’s population.

20. Luristan Newt (aka Kaiser’s Spotted Newt)

The luristan newt is a type of salamander and is endemic to the southern Zagros Mountains in Iran. The luristan newt is coveted in the pet trade — they were sold on a Ukraine website for $300 — and now only survives in captivity.

25. Saola

Hunting in the Saola’s habitat has caused the species’ population to decline.

26. Red River Giant Softshell Turtle

Na Son Nguyen / AP

This enormous weighs 440 pounds. Unfortunately, there are only four red river giant softshell turtles left, all of which live in captivity. The animal is considered sacred by many Vietnamese.

27. Dusky Gopher Frog

Gerald Herbert / AP

The entire population is estimated to be between 60–100 individuals living in two ponds in Mississippi. Unfortunately, the dusky gopher frog population has declined because of loss of wetlands and native longleaf pine habitat, the decline of gopher tortoises, invasive species, disease, drought conditions, and lack of natural and prescribed fire.

32. Parides Burchellanus

There are fewer than 100 parides burchellanus left living in Cerrado, Brazil.

33. Franklin’s Bumblebee

Eter Schroeder / AP

Franklin’s bumblebee lives in Oregon and California. This bumblebee is threatened by disease from commercially bred bumblebees and habitat destruction.

34. Common sawfish

TORSTEN BLACKWOOD / Getty Images

The common sawfish lives in the coastal tropical and subtropical waters of the Indo-Pacific and Atlantic oceans. Currently, the common sawfish is largely restricted to northern Australia.

Rob Griffith / AP

Sawfish have adapted to live in both salt and fresh water, while their long saw-like rostrum (nose) has evolved to expertly forage for food under the sandy ocean floor. Sawfish have been placed on the critically endangered list mainly due to a human impact to their environment and being entangled in fishing nets.

35. Tonkin Snub-Nosed Monkey

The tonkin snub-nosed monkey is endemic to Northeastern Vietnam, where there are fewer than 200 left.

Tilo Nadler / AP

Heavy poaching and the destruction of habitat have diminished this monkey’s population.